survivors suffered through four days of sheer terror and some are just beginning to recuperate at this nato base. they were beaten, tied up and executed. the survivors are shocked and shaken. >> it happened so fast. >> reporter: they saw horrifying scenes and one foreigner was used as bait to lure his co-workers out before being shot. steven mcfall had his mouth taped and wore explosives taped to his chest and mark grant hid for 80 hours and scrambled up on the roof or locked themselves inside their rooms. >> we barry indicated together in one of the offices we lock the door we put a deck on the door. we did a barley cade. >> reporter: when they got out, joy and relief. >> when the guys who picked up, the rescue guys were wonderful. we were like long lost friends. >> reporter: one survivor's family says they have been through hell and when one son heard his father was alive it was the best news he'd ever heard. dan? >> nick schifrin, thank you. bianna, over to you. >> terrifying week. >>> we'll turn now to the countdown to president obama's second inauguration. tomorrow hundreds of thousand